Spatiotemporal variation in the impacts of biological invasions

生物入侵影响的时空变化

• 批准号: RGPIN-2016-03918
• 负责人: Ricciardi, Anthony
• 金额: $ 3.79万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=690362
• 关键词: Spatiotemporal; variation; impacts; biological; invasions

Nonindigenous species are being discovered in aquatic ecosystems at increasing rates worldwide. Many of these invasions appear to have minor ecological effects, while others cause substantial changes to biodiversity and food webs. Our capacity to predict which invasion will have undesirable consequences is impeded by context dependence: invader impacts vary across space and time under the influence of local environmental conditions. The long-term goal of my research program is to develop models that explain and predict the impacts of biological invasions. The aim of this proposal is to explore context dependency by testing hypotheses that explain spatiotemporal variation in impact. Three major hypotheses are the focus of this proposal: 1) the Invasion Front Hypothesis predicts that more recent invaders such as those at the front of a spreading population will exert higher impacts associated with higher feeding rates and heightened aggression, whereas individuals from longer established core populations will be less voracious and aggressive; 2) the Environmental Matching Hypothesis predicts that an invader will produce stronger per capita effects in an abiotic environment that closely matches its physiological optimum; and 3) the Resource Consumption Hypothesis predicts that the most disruptive invasive species have higher and more efficient resource consumption rates than those species without extensive invasion or impact histories.******I will use a combination of lab and field experiments on fishes and crustaceans in a variety of freshwater and marine habitats as model systems. Treatments with increasing prey abundances will be offered to invasive predators, and the number of prey consumed will be related to prey supplied in a classical functional response experiment that will allow us to quantify per capita effects. Context dependency will be incorporated by comparing per capita effects across gradients of temperature, water chemistry and water velocity. These lab experiments will be complemented by field mesocosm experiments involving reciprocal transplants between the invasion front and core sites where the invader is well established. Field sites will incorporate natural environmental gradients. ******In testing these hypotheses, my lab will identify and develop some valuable model systems that can be used to inform invasion theory, and we will demonstrate how environmental context can be incorporated into risk assessment.

在世界范围内，在水生生态系统中发现非本地物种的速度越来越快。其中许多入侵似乎对生态产生了轻微的影响，而其他入侵则对生物多样性和食物网造成了重大变化。我们预测哪些入侵会产生不良后果的能力受到环境依赖的阻碍：在当地环境条件的影响下，入侵者的影响在空间和时间上是不同的。我的研究项目的长期目标是开发能够解释和预测生物入侵影响的模型。本提案的目的是通过检验解释影响时空变化的假设来探索上下文依赖性。主要有三个假说：1)入侵前沿假说预测，较新的入侵者，如那些处于扩张种群前沿的入侵者，将产生更高的影响，与更高的摄食率和更高的攻击性相关，而来自较长时间建立的核心种群的个体将不那么贪婪和具有侵略性；2)环境匹配假说预测入侵者在与其生理最优匹配的非生物环境中会产生更强的人均效应；3)资源消耗假说预测，破坏性最强的入侵物种比没有广泛入侵或影响历史的物种具有更高和更有效的资源消耗率。******我将结合实验室和实地实验，在各种淡水和海洋栖息地的鱼类和甲壳类动物作为模型系统。将为入侵掠食者提供增加猎物丰度的处理方法，并且在经典的功能反应实验中，消耗的猎物数量将与猎物供应相关，这将使我们能够量化人均效应。通过比较温度、水化学和水速度梯度的人均影响，将纳入环境依赖性。这些实验室实验将辅以现场中观实验，包括入侵前沿和入侵者已经建立的核心部位之间的相互移植。现场场地将结合自然环境梯度。******在测试这些假设时，我的实验室将识别和开发一些有价值的模型系统，可用于告知入侵理论，我们将演示如何将环境背景纳入风险评估。